Analysis of imidacloprid and pyrimethanil in shallot (Allium ascalonicum) grown under greenhouse conditions using tandem mass spectrometry: establishment of pre‐harvest residue limits

Abstract

In this study, the original Quick, Easy, Cheap, Effective, Rugged and Safe method was used for the extraction of imidacloprid and pyrimethanil followed by a rapid clean-up through dispersive solid-phase extraction technique with primary secondary amine sorbent and magnesium sulfate in shallot. Residues were analyzed using LC-tandem mass spectrometry in positive-ion electrospray ionization mode. The limits of detection and quantification were estimated to be 0.006 and 0.02 mg/kg, respectively. The samples were fortified at two different concentration levels (0.2 and 1.0 mg/kg), and the recoveries ranged between 79.7 and 83.9% with relative standard deviation values < 6%. The method was successfully applied for the establishment of the pre-harvest residue limits (PHRL). The rate of disappearance of imidacloprid and pyrimethanil on shallot was described with first-order kinetics (imidacloprid, y(2) = 0.9670; pyrimethanil, y(2) = 0.9841), with half-lives of 2.87 and 2.08 days, respectively. Based on the dissipation patterns of the pesticide residues, the PHRL was recommended at 7.86 mg/kg for 14 days (PHRL14 ) and 1.98 mg/kg for 7 days (PHRL7 ) before harvest for imidacloprid, and 21.64 mg/kg for 7 days (PHRL7 ) and 9.28 mg/kg for 4 days (PHRL4 ) before harvest for pyrimethanil in shallot.

Analytical approach, dissipation pattern and risk assessment of pesticide residue in green leafy vegetables: A comprehensive review

“…MRMs and SRMs involve the same fundamental steps. However, MRMs are usually applied to monitor or screen various classes of pesticides in commodities, whereas SRMs are applied for individual pesticides in specific crops to determine half‐lives, dissipation patterns, PHI and PHRL (Jang et al, ; Park et al, ; Rahman et al, , Rahman, Na, et al, ; Siddamallaiah & Mohapatra, ). Therefore, for the purposes of safety and dietary risk assessment, an effective analytical method must be developed to quantitatively determine the parent compound and its metabolites, if any, in specific crops, even though the metabolites are not included in the definition of residue.…”

“…PHRLs have been established by the National Agricultural Products Quality Management Service (Gimcheon, Republic of Korea) and incorporated with pesticide MRLs to prevent the distribution of agricultural products that exceed the MRLs (Chang et al, ). The PHRL uses an estimate of the pesticide residual quantity applied during the pre‐harvest period and determines the pesticide residual quantity at the time of harvest by calculating the biological half‐life and dissipation constant (Al Mahmud et al, ; Chang et al, ; Chung et al, ; Farha, Rahman, Abd El‐Aty, Jung, et al, ; Farha, Rahman, Abd El‐Aty, Kim, et al, ; Kabir et al, ; Kabir et al, ; S. W. Kim, Abd El‐Aty, et al, ; Namgung et al, ; Park et al, ; Rahman, Na, et al, , , ; Truong et al, ). The PHRL was computed by an automatic computational method using a statistical procedure in SPSS ().…”

“…The automated system calculates the decay constant required for estimating the PHRL. Because of the upper and lower bounds of the regression coefficient ( −k ) at 95% confidence level, the aforementioned method was used for calculating the decay constant with the help of the upper bound of the agricultural products (Park et al, ).…”

Development a monoclonal antibody-based enzyme-linked immunosorbent assay for screening pyrimethanil in fruits and vegetables

“…Due to their broad spectrum of fungicidal activity, pyrimethanil is widely used to control a wide range of postharvest fungal diseases on fruits, vegetables and ornamental crops (Shim, Abd El-Aty, Choi, & Kang, 2007). Abuse of pyrimethanil has been reported to cause deleterious effects on humans, livestock, crops and the environment (Fenik, Tankiewicz, & Biziuk, 2011;Park et al, 2013). Therefore, maximum residue limit of 0.2-10 mg/kg for pyrimethanil in food products has been implemented in many countries and regions, including the EU, USA and China (Liang et al, 2013;Mandrile et al, 2018).…”

Quick, easy, cheap, effective, rugged, and safe sample preparation approach for pesticide residue analysis using traditional detectors in chromatography: A review

“…Multiresidue methods (MRMs) and single‐residue methods (SRMs) generally consist of the same basic steps. However, MRMs are usually applied to monitor or screen various classes of pesticides in some commodities, whereas SRMs are applied for individual pesticides in specific crops to investigate the half‐life, dissipation pattern, pre harvest interval (PHI), and pre harvest residue limits (PHRL) .…”